Everything about Vasily Grossman's novel, Life and Fate is epic. It's 900 pages long. It was deemed so dangerous when published in 1959 that the KBG arrested the book itself, and even confiscated the typewriter ribbons Grossman had used. Praise from its fans is dizzying, with the book described by many as the most important of the 20th century. And Radio 4 has this week for the first time ever given all of the station's drama slots – bar The Archers – over to an eight-hour dramatisation of it.

Andrew Marr, on Feedback last week, recalled the moment Mark Damazer – the former Radio 4 controller who was responsible for this immersive approach to the drama – pressed a copy of the novel onto him, saying, "If you want to be a serious person, you have to read this book".

Radio 4 is clearly hoping that the serious people in its audience will have the will and stamina to stick with an unflinching drama across 13 slots of varying lengths (Woman's Hour drama, Classic Serial, Afternoon Play) dotted throughout the week and ending on Sunday. To follow it as it has been broadcast so far takes some preparation and organisation; never before have I printed out a family tree to accompany a radio play, or missed other favourite shows to keep up with one. And listening in public has its perils, too. I sobbed on a busy train during Monday's Woman's Hour drama, as Janet Suzman read a a letter from a mother behind the barbed wire of a Jewish ghetto in the Ukraine to the son she knew she'd never see again. It was one of the most haunting segments of the whole week.

One of the many things that makes this all-encompassing adaptation work so brilliantly is its segmented structure: densely packed into a week, sure, but really only amounting to about an hour a day. You need the gaps between to absorb, and sometimes recover from, the intensity. Mike Walker and Jonathan Myerson's adaptation homes in brilliantly on Grossman's blend of huge themes and epoch-shaping events with small snapshots of ordinary life, as he traces the fate of one middle-class Russian Jewish family against the background of the battle of Stalingrad.

Because these moments of being – the fizzling out of a love affair, progress in a career, the pain of losing a child, the sudden certainty of death approaching – stand at the core of each episode, each part also succeeds as a standalone drama, and can be listened to out of sequence. You can also download the whole adaptation, which is currently topping the iTunes podcast chart in the UK.

But really this week's experiment demonstrates once again the power of radio drama. Life and Fate represents the peak of what it can do, given time – the project was delayed for a year to wait for Kenneth Branagh – budgets and a jaw-dropping cast (Suzman, Branagh, Harriet Walter, David Tennant, Greta Scacchi, Samuel West). It tells stories that are immediately real, vivid, heartbreaking and illuminating about one of the darkest interludes in our history, and does so with commanding skill.

Part of the magic is that Life and Fate is currently a little-known novel, so most of us come to listening without preconceptions or expectation. That lets the imagination soar as it does with the very best radio plays, and what a luxury to do so with such dramatic riches. This is a tough book, shaped by Grossman's own experience – his mother was among 20,000 Jews murdered in Berdichev in 1941 – and his time as a war correspondent, during which he wrote one of the first eyewitness accounts of a Nazi extermination camp. It can make grim listening in places, but this is countered by beautiful writing, exquisite acting and the sheer class of the adaptation. If this doesn't clean up at the Sony Awards, I'll eat my DAB.